1. Field of the Invention
The present invention relates to a stent graft.
2. Relevant Technology
Stent grafts generally comprise an inner stent and an outer stent using similar wall structures including the same strut-patterns and a flexible membrane or stretchable material layer interposed between the inner and outer stent. When the balloon of the catheter is inflated the inner stent is less expanded than the outer stent and therefore physically exhibits a bigger recoil force compared to the more expanded outer stent. Hence the smaller radially acting contact force of the expanded inner stent onto the outer stent deteriorates the desired connecting performance of the stent-graft. Furthermore stent-grafts having thinner walls to be more flexible are often damaged or destroyed during welding to fix both stents to one another